(Georgia Institute of Technology, 2000-11-20)
Wang, Z. L. (Zhong Lin); Dai, Z. R.; Gao, Rui Ping; Bai, Zhigang; Gole, James L.
Elevated-temperature synthesis has been used to generate side-by-side biaxially structured silicon carbide–silica nanowires. The axial growth direction approaches [311] for nanowires with a high density of microtwins and is [211] for defect-free nanowires. The structure of these nanowires, their cross-sectional shape, and their structural transformation between a biaxial and coaxial configuration have been studied by transmission electron microscopy. The Young's modulus of the biaxially structured nanowires was measured to be 50–70 GPa depending on the size of the nanowire.
(Georgia Institute of Technology, 2000-04-24)
Gole, James L.; Stout, J. D.; Rauch, William L.; Wang, Z. L. (Zhong Lin)
Elevated temperature synthesis has been used to generate virtually defect free SiO₂sheathed crystalline silicon nanowires and silica (SiO₂) nanospheres which can be agglomerated to wire-like configurations impregnated with crystalline silicon. The SiO₂ passivated (sheathed) crystalline silicon nanowires, generated with a modified approach using a heated Si–SiO₂mix, with their axes parallel to 111 are found to be virtually defect free. Modifications to the system allow the simultaneous formation of SiO₂ nanospheres (d~10–30 nm) as virtually monodisperse gram quantity powders which form large surface area catalysts for the selective conversion of ethanol to acetaldehyde.